Expandable Polyaxial Spinal Pedicle Screw System
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Solution Overview
Problem
Current spinal pedicle screw systems are often associated with spinal fusion, which has negative impacts and does not address scoliosis effectively, necessitating a non-fusion system that can prevent or correct scoliosis while maintaining spinal motion.
Innovation Solution
An expandable spinal pedicle screw system that includes distraction rods with polyaxial joints and fasteners, allowing for expansion after screw insertion and maintaining spinal motion through polyaxial joints, while preventing fusion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If standard pedicle screws system is used for spinal fusion, then spinal stability is improved, but spinal motion is lost and negative impacts occur
Solution Approach 1:
The pedicle screw system incorporates polyaxial joints that allow dynamic motion between connected elements. The joints enable axial rotation and angular movement while maintaining structural stability, transforming the static fusion system into a dynamic construct that preserves spinal mobility.
Solution Approach 2:
The spinal system is divided into modular components including pedicle screws, polyaxial joints, and distraction rods that can be independently positioned and adjusted. This segmentation allows each component to fulfill specific functions while collectively maintaining both stability and motion capability.
2Shape
If pedicle screws are inserted to correct scoliosis, then spinal alignment is improved, but spinal motion is restricted
Solution Approach 1:
The polyaxial joints enable the system to achieve proper spinal alignment while preserving natural motion. The joints allow for multi-directional adjustment during alignment correction and maintain flexibility for physiological movement after correction is achieved.
Solution Approach 2:
The system utilizes adjustable parameters including distraction rod length, polyaxial joint angles, and screw positioning to achieve optimal spinal alignment. These parameters can be modified intraoperatively to correct deformity while preserving motion capabilities.
3Length of moving object
If distraction rods are expanded after screw insertion, then distance between screws is increased, but device complexity increases
Solution Approach 1:
The distraction rods feature an expandable design with collapsible segments that can be compressed during insertion through the pedicle canal and then expanded to the desired length after positioning. This dynamic transformation simplifies the insertion process while achieving the required distraction distance.
Solution Approach 2:
The expandable distraction rod employs a telescoping structure where segments nest within each other during the insertion phase, allowing the rod to pass through confined spaces. After positioning, the segments are deployed outward to achieve the final expanded configuration.
Data Source
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AI summary
A spinal pedicle screw system includes distractions rods and has the ability to be distracted after the screws are inserted into the pedicle and maintain polyaxial motion via poly axial joints.